Acridine compounds and process of making the same



Patented July 5, 1949 Joseph H. Burekhalter, jDetroit, Eldon M. Jones \and Albert L. Rawlins, Grosse Pointe Woods, Frank H. Tendick, Grosse Pointe Park, and Walter F. Holcomb, Detroit, Mich, assignors to Parke, Davis & Com

No Drawing. Application pany, petroit, Mich., a cor- -poration ofllflichi'gan J nuar 45 SerialNo. 53 ,96; 14 Claims. (crest-2w) 1 This application is a continuation-in-part of copending application, Serial No. 539,990, filed June 12, 1944, and relates to certain new acridine derivatives and is particularly concerned with substituted acridineshaving the general formula,

wherelfiis hydrogen, lower alkoxy or lower alkyl, R1 is hydrogen, lower alkoxy or lower alkyl, R2 .is hydrogen, halogen gor CN, R3 ;is hydrogen, halogen lowergalkyl or lower ,alkenyl and R4 and .Rs are ,thasamQprldi-fierent and represent hydro en, valkyl iradical l ontain n not m r than A lear pn atoms, hyd o ylal radica n a nin wnotimoretham carbon; t msto Whe tak n t0- iae ther with -:.a h teroc cl .rin tsu ias m rpholinelsp peridine. P peraZine and thiomqr- "pholi Theea ridin tcempound o lthelpre n i nrention mars be prepa ed :by o den in qu mola :no it pn wf a tsiihstitu edliar amine 1 he ein fte "reter dito: a 1 comp u 11 a a tha oa rid a ah r ieaite r re er-twat! a m xnnq n l 1;?

abl swea @The wtmmw b c rrie fiw in t-tli lrteseeq o alkal n rn tra on qidi lmei and the reaction h i raph call lre resented as follows:

where R, R1, R R3, R4 and R5 have the same significance as "given above the Xrepresents' a hal'onatbin suoh as chlorine, bromine or iodin. W brfer to carry 'out the reaction in themes; ence of a dilute or concentrated organic acid or aldili'ite inorganic acid. Anothern ethod for the preparation of the wiaineedmpounds of the presentinventior'i, whichiis, in effect, a variation'of theaboveusirig aoidic' inedium, involves the reaction of the 'ar'ni ioiiheriol and Y a -chloroacridin in phenolic i'riedii im. The desired product' may -be"preci1i ftjat'ed from an ether suspension of the reaction 'miiiturefloy the addition of hydrogen chlori'deI "Another method 'of obtaining acridine coin- ';poun'ds* according to this invention involves the direct condensation of "an N-acy'l derivative of with a 9-ha1oacridine in acid solution. This reaction may be represented graphically as follows:

where R, R1 R2, R3, R4, R5 and X have the same "significance t.,asg iyen above. JIIhis process inwires h simu anequs h drol of a ylete o mmu an condens t o o t resu in amin lw 'h zf low n zexa e i u t a th ttio ahu ido n t h wers ..lim i here "chloro-acridine suspended in alcohol.

Example 1.--2-methoxy-6-chZ0r0-9-(4'-hydromy- 3'-dz'ethylaminomethyl 5'- allylamlz'no) acridz'ne dihydrochlorz'de 13.8 g. (0.05 mole) of 4-acetamino-2-al1yl-6- diethylaminomethylphenol is boiled under a reflux condenser for one hour with 50 cc. of 6 N hydrochloric acid. The solution is cooled and treated with strong caustic soda solution until just acid to Congo red, and diluted to about 100 cc.

I To this solution is added 13.9 g. (0.05 mole) of powdered Z-methoxy-6,9-dichloroacridine and the mixture heated on the steam bath for two hours, with frequent stirring. During this time the mixture becomes dark red in color. The unreacted acridine is removed by filtration from the hot solution and after cooling the filtrate is treated with an excess of ammonium hydroxide. The free base is extracted with a total of 21. of ether, dried over solid potassium carbonate, filtered and the filtrate evaporated to a volume of 1 liter. This is chilled and treated with excess hydrogen chloride in absolute alcohol. The dihydrochloride separates as a dark red, gummy mass which solidifies on standing. This is separated from the ether, boiled with a little methanol and diluted with an equal volume of acetone. n cooling the solution and rubbing with a glass rod, the product separates as a bright red powder. After re- U crystallization the product melts as 233 C. dec.

Example 2.2-methoacy 6 chZoro-9-(3'-ethylaminomethyl 4-hydroa:yam'lmo) -acrz'dine dihydrochloride JHzNH C 2 An aqueous solution of 14 g. of 2-ethylaminomethyl-4-aminopheno1 dihydrochloride is adjusted to pH 3 and then warmed for two hours in a steam bath with 14 g. of 2-methoxy-6,9-di- The solvent is decanted from the oily product and the oil then triturated under acetone until crystallization is induced. The orange colored dihydrochloride is recrystallized from methanol.

Example 3.--2-methowy 6 chloro-9-(3'-amino- 15 methyl 4-hydroxyanilino) -acridine ding drochloride OH OH CHzNC 0 05115 CH2NH2 N02 NH;

CHzNHz 0H30 l CH2NHI c1130 I A suspension of 7 g. of 2-benzoylaminomethyl- 4 4-nitrophenol lEi'nhorn, Ann., 343, .242 (1906)] and 0.1 g. of platinum oxide catalyst in cc. of alcohol is shaken on a hydrogenation machine until the theoretical amount of hydrogen has been absorbed. The catalyst is then removed by filtration and the filtrate refluxedwith 25 cc. of concentrated hydrochloric acid for 24 hours. This solution, which contains Z-aminomethyl-l-aminophenol, is treated with concentrated alkali to raise the pH to about 3, and then 6 g. of 2-methoxy-6,9-dichloro-acridine is added. The mixture is heated for an hour on a steam bath. After cooling, the product is collected, triturated well with water and recollected. After Washing with alcohol and acetone, the orange dihydrochloride is recrystallized from alcohol.

Example 4. 2-methoxy-6-chloro-9-[3,5' bis- (diethylaminomethyl) 2 hydrozyamlinolacrz'dine trihydrochloride A mixture of. 23 got 2,4-bis-(diethylaminomethyl) -6-acetaminophenol and 50 cc.of.conceI 1- trated hydrochloric acid is refluxedlfor an hour. The pH of the solution is adjusted to about 4by the addition of concentrated alkali, and 19 g. of Z-methoXy-6,9-dichloroacridine suspended in 50 cc. of alcohol is then added. This mixture is heated for a period of three hours on a steam batlr (the pHgradually drops during the first part of the period). After standing for a few hours, an orange trihydrochloride separates and is purified by recrystallization from methanol-ether, M. P. 257 C. dec. v

Purification, especially. for the removal of sodium chloride and the insoluble acridine, may also be effected bytreatmenttof the crude trihydrochloride with concentrated ammonia and extraction of the free base with ether. The extract is washed wellwwith water and then dried over anhydrous potassium carbonate. The filtered solution is treated withan excess ofalcoholic hydrogen chloride and the precipitated tri hydrochloride is further purified by dissolving in warm methanol and precipitating with ether.

Eirample 5.2,3dimethyl 6 chZor-9(4-hydreary-3"-diethyldmmomethylanilino) acridine cliitydrochloride @11 CH2N(C H)2 acid i hydrolysis C H C1 then 3 coupling- N HG OCHa C HgN C EH5) I NH CH3 N C1 16.52 g. (0.075 mole) of. 2-diethylaminomethyl- 4-acetylaminophenol is refiuxedfor one hour ina. solution of. 75 cc. concentrated hydrochloric. acid, 75 cc. water and 60. cc. ethanol. ThepHof the solution is then adjusted to 4 with 40% sodiurn. hydroxide solution. 18.35 g. (0.07 mole) of 2,3- di'methyl-6,9-dichloroacridine, M. P. 121 C. dec., is added and the resulting suspension refluxed for l' hour. The ethanol is distilled in vacuo, and the free base liberated from the aqueous solution of the hydrochloride by adding excess sodium carbonate. This product is extracted withether, filteredto remove the insoluble" acridine, and the ether layer dried over anhydrous magneSiumsuI- fate. After filtration, anhydrous hydrogen chloride is admitted to the filtrate whereupon the dihy'drochloride precipitates. The product is collected and dried at 70 C. Purification is effected by dissolving the salt in a minimum of drymethyl alcohoh heating, adding sufiicient warm acetone to effect incipient crystallization, and. cooling slowly; M. P. of. thepuresa1t..259 263 C. dec..

Example 6i-2 mthomy- 6 cElbm=9a gh ydmmya 3' cliethylaminometlwl s terir bdtyld'nilmo) acridine dihydrochloride' w h A- mixture of 7' g. of 2-diethylaminometliyl w tert;-butyl" 6 e acetaminophenol hydrochloride (M; P. 158"" C.) and 14cc. of concentratedhydrmchlori'c acid ishe'ated at refiuxingxtemperaturefor an" hour; The pH of the; solution is adjusted to" 3 or e by the addition of concentrated sodium hydroxide solutionarid 515g; of z methoxy-dm dichloracridlne suspended in cc. of alcohol is. added. Thezmixtureisuheatd at 100 C. foran hour. Upon cooling, the orange dihydrochlor'ide separates as an oiltwhich soon crystallizes. The product is purified by dissolving in warm methanol andreprecipitation by theaddition of acetone; M. P. 270 C. dec.

Example 7 .2-mthoa:y- 6-chZoro-9- (3 diethylaminomethyl-fl hydrowy 6' chlorocmilino) acrz'dine dz'hydrochloride on o A c1 ommoznm omo- N/ -01 I'm,

A mixture of ll g. of2-diethylaminomethyl4 amino-fi-chlorophenol; v13 g. of 2-meth-oxy-6,9-" dichloroacridineaandtfill gLLoi phenol is heated at 100 C. for two hours. The; reaction rnixt-ure'is poured into a large 'volume of ether and an eic cess of. alcoholic hydrogen chloride added to prev. cipitatet the dihydrochloride salt. The orange? p oduct is. recrystallized trom methanol; Ma Pa 290 C. dec. i

Hll

T BIN Z 2 s)2 CHaO i e i 2,474;s19

Example 8.-:2-methoa:y-6-chloro-9-(3' diethylaminomethyl-2'-hydroxy 5 phenylam'lmo) acridine dihydrochloride OH 01 T nHs p y i 011 CH2N(C2H5)2 Ewa mple 9.--2-metho$y-6-chlor0-9-(3'-N-piperidylmethyl-ei'-hydroa:yanilino) acrz'dine (tinydrochloride i 2 OH OH 5 CH2NC5H1o CE NCaHm i E i e N02 NH: H E 01 iN a -w CHaO- i E 01 i N will I CHzNCaHm CF30- A suspension of 6.2 g. of Z-N-piperidylmelthyl- 4-nitrophenol (M. P. 104 C.) and 0.1 g. ofialatinum oxide catalyst in 100 cc. of absolute alcohol is shaken on a hydrogenation machine until the theoretical amount of hydrogen is absorbed. The catalyst is removed by filtration and dilute hydrochloric acid added until a test with pH paper indicates definite acidity. T I

To the acidified solution containing Z-N-piperidylmethyl-4-aminophenol 6.4 g. of Z-methoxy- 6.9-dich1oroacridirie is added. The mixture is heated in a steam bath for about three hours during which time a clear solution is effected followed by precipitation of the desired product as an orange dihyglrochloride. After recrystallization from methanol, the product is collected on a funnel and washed with methanol and acetone; P. 287 0. dec.

. Exdmplel0.-2-methomy-6-chloro-9-(3' as hydromyethylaminomethyl 4 hydromyanz'lz'no) acridine dihydrochlorz'de *OH i -oH2NHoH,oH,oH 011:0

CHaO

A mixture of 6.2 g. of Z-B-hydroxyethylaminomethyl-gl-acetaminophenol hydrochloride (M. Pd 224) and 17 cc. of concentrated hydrochloric, acid is *heated at boiling temperature for an hour. The solution is cooled somewhat and the:

acidity adjusted to about pH 4 by the addition of strong alkali solution. To the hydrolysate, 8.35 g. of 2-methoxy-6,9-dichloroacridine suspended in 20 cc. of alcohol is added and the mixture heated in a steam bath for over an hour. The

1:recipitated orange dihydrochloride is collected and recrystallized from methanol; M. E 282 C.

dec.

Example 11 .9- (4 'hydromy-t iethylmpinoethylanilz'no):acridine dihydrochloride By reacting Q-chIoro acridine with Z-diethyL: aminomethyl-4=aminophenol dihydrochioride in the manner described in Example 1, fi-( lH-hy droxy 3 diethylaminomethylanilino)5 acridine i dihydrochloride is obtained; M. P. 265 6. dec.

T Other compounds of this inventiorg may be prepared in a manner similar tcfithat shown in the above examples by condensing Icompounds P and H. The following are representative examples of compounds P: I

phenol i i I i 2-diethylarninomethyl-4-amino-6 butylphe- 5101 i 2 liethylaijiinomethyl-fi-aminophenol 9. z-dimethylaminomethyii-aminophenol 10. 2-di-(c-hydroxyethyl) aminomethyl 4 aminophenol 11. 2-ethylaminoethyl4-aminophenol 12. 2-N-piperazinomethyle4-aminophenol 13. 2-N-thiomorpholinylmethyl4aminophenol The following are representative examples of compound H:

1. Z-methoxy-6,9-dichloroacridine 2. 2methoxy6-cyano-9-chloroacridine 3. 2,3-dimethyl-6,9dichloroacridine 4. 2,3-dimethoxy-6,9-dichloroacridine The compounds of this invention are useful therapeutic agents and, in general, they are characterized by their toxicity to protozoa, particular,- ly plasmodia. These new compounds may be used in the form of their salts of hydrochloric acid, sulfuric acid, prosphoric acid, sulfamio acid, acetic acid, lactic acid, tartaric acid, gluconic acid, citric acid, and alkyl sulfonic acids or as the insoluble salt of methylene disalicylic acid.

Attention is directed to applicant's copending applications, Serial No. 539,990, filed June 12, 1944 now Patent No.2,428,355, issued October 7, 1947, and Serial No. 629,713, filed November 19, .1945, wherein certain acridine compounds somewhat related to the compounds of the instant application are describedand claimed. Attention is also directed to other copending applications wherein certain quinoline compounds are described and claimed as follows: Serial No. 556,496, filed September 29, 1944; Serial No. 576,900, filed February 8, 1945; Serial Nos. 626,906, 626,907 and 626,908, all filed November 5, 1945; and Serial NO.

722,474, filed January 16, 1947.

What we claim as our invention is;

1. A compound of the class consisting of a free base and its acid addition salts, Said free base having the formula,

011 R4 lom ml I 1...

where R is a member of the class consisting of hydrogen, lower alkoxyand lower alkyl radicals, R1 is a member of the class consisting of hyrogen, lower alkoxy and lower alkyl radicals, R2 is a member of the class consisting of hydrogen, halogen and -CN, R3 is almember of the class consisting of hydrogen, halogen, lower alkyl and lower alkenyl radicals, R4 and R5 are members of the class consisting of hydrogen, alkyl radicals containing not more than 4 carbon atoms, hydroxy alkyl radicals containing not more than 4 carbon atoms and further members wherein R4 and R5 together with N form a heterocyclic rin f the lass consistin of mo pholin pip ri din pipe azinc and. thiomorph line and the group is in one of the positions ortho and para to the wOI-I groups.

2. An acid addition salt of a free base, said free base having the formula,

wh e R is a memb of, th c ss c nsis i g f hyd ogen, ower alkoxy an low alk l a icals. R1 is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R2 is a member of the class consisting of hydrogen, halogen and CN, R3 is a member of the class consisting of hydrogen, halogen, lower alkyl and lower alkenyl radicals and R4 and R5 are members of the class consisting of hydrogen, alkyl radicals containing not more than 4 carbon atoms, hydroxy alkyl radicals containing not more than 4 carbon atoms and further members wherein R4 and R5 together with .N form a heterocyclic rin of th c ass cons s ing o morpholine. iperi: dine, piperazine and thiomorpholine.

3. A compound of the class consisting of a free base and its acid addition salts, said free base having the formula,

4. A compound of the class consisting of a free base and its acid addition salts, said free base having the formula,

A com nd o the l ss consisting i a tree base and ts cid add tion sal sa free base av ng t e fo mula,

NHQOH omNni 6. A compound having the formula,

oHhoH=o i 7. A compound having the formula,

8. A compound having the formula,

1 X CHZNHI C1130- 9. Process for obtaining a compound of the class consisting of a free base and its acid addition salts, said free base having the formula,

which comprises reacting a 9-haloacridine compound of the formula,

R1" N/ R2 with a substituted aminophenol of the formula,

OH R4 CHzN I R \R 3 l where X is a halogen atom, R is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R1 is a member of the class consistin of hydrogen, lower alkoxy and lower alkyl radicals, R2 is a member of the class consisting of hydrogen, halogen and -CN, R3 is a member of the class consisting of hydrogen, halogen, lower alkyl and lower alkenyl radicals, R4 and R5 are members of the class consisting of hydrogen, alkyl radicals containing not more than 4 carbon atoms, hydroxy alkyl radicals containing not more than 4 carbon atoms and further members wherein R4 and R5 together with -N form a heterocyclic ring of the class consisting of morpholine, piperidine, piperazine and thiomorpholine and the which comprises reacting a 9-halocridine com- J Rs pound of the formula,

with a substituted aminophenol of the formula,

log CHaN in the presence of dilute mineral acid, where X is a halogen atom, R is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R1 is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R2 is a member of the class consisting of hydrogen, halogen and CN, R3 is a member of the class consisting of hydrogen, halogen, lower alkyl and lower alkenyl radicals, R4 and R5 are members of the class consisting of hydrogen, alkyl radicals containing not more than 4 carbon atoms, hydroxy alkyl radicals containing not more than 4 carbon atoms and further members wherein R4 and R5 together with -N form a heterocyclic ring of the class consistin of morpholine, piperidine, piperazine and thiomorpholine and the /R4 -CHzN s group is in one of the positions ortho and para to the -OI-l group.

11. Process for obtaining a compound of the class consisting of a free base and its acid addition salts, said free base having the formula,

| i /R R- HaN which comprises reacting a 9-haloacridine compound of the formula,

where X is a halogen atom, R is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R1 is a member of the class consisting of hydrogen, lower alkoxy and lower alkyl radicals, R2 is a member of the class consisting of hydrogen, halogen and CN, R3 is a member of the class consisting of hydrogen, halogen, lower alkyl and lower alkenyl radicals and R4 and R5 are members of the class consisting of hydrogen, alkyl radicals containing not more obtaining a compound of the class consisting 13 than 4 carbon atoms, hydroxy alkyl radicals containing not more than 4 carbon atoms and further members wherein R4 and R5 together with N form a heterocyclic ring of the class consisting of morpholine, piperidine, piperazine and thiomorpholine.

12. The process which consists in condensing a compound having the formula,

N or

with a compound having the formula,

om-o11=orn mN 0H omen.

C H: 0 B3 obtaining a compound of the class consisting of a free base and its acid addition salts, said free base having the formula,

CHaOH;

NH OH cmo H:N

CHaCH N/ 01 13. The process which consists in condensing a compound having the formula,

CHgO- with a compound having the formula,

NH on H NE 0 1H;

a. free base and its acid addition salts, said free base having the formula,

14. The process which consists in condensing a compound having the formula,

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,113,357 Mietzsch et a1 Apr. 5, 1938 

